a11y-tests

a11y-tests is a Javascript library for testing the basic accessibility of your website. It's customizable and framework-agnostic, so you can drop it into your existing code and integrate it quickly.

Using the test framework

Include a11y.js in your project and call window.$A11y.checkA11y(...) to test your HTML. Calling window.$A11y.checkA11y() with no parameters will run all tests on the entire document, but checksToRun has three parameters that allow you to customize how tests are run:

• domElem: By default, checkA11y will run on the entire document. If you pass in a DOM element here, it'll only run tests on that element and all DOM nodes within it.
• checksToRun: By default, checkA11y will run every single test, or whatever's included in the defaultChecksToRun array. If you only want to run a subset of tests, pass in an array of their test tags.
• dontShowErrors: By default, checkA11y will put a red border around each element with an error on the page. Set this parameter to true if you'd rather not have that happen.

Adding your own tests

Each test has its own unique tag. We've given all our tests a tag A11Y_DOM_{{number}}, but you may want to create your own tagging convention for custom tests.

1. Add your new test to the testFunctions object like so:

testFunctions : {
  {{yourTestNameVariableHere}} : {
     "tag"  : {{yourTestTag}},
     "func" : function(domElem) {
        var errorArray = [];
        
        // add code here to test the given domElem and all its child nodes for
        // a particular error and add them to the errorArray if necessary
          
        return $A11y.util.formatOutput(errorArray, this.tag);
     }
  }
  ...
}

Helper functions should live in the util object.

2. In the errorMessages map, create a mapping between your test tag and a brief error message:

   errorMessages : {
     "A11Y_DOM_01": "All image tags require the presence of the alt attribute.",
     {{yourTestTag}}: {{a short helpful error message}}
     ...
   }
   

3. Add a longer explanation of the error and how to fix it in the examples documentation (coming soon!).
4. Add the test's tag name to the `defaultChecksToRun` array.
5. Test your tests! Add test cases to the `test.js` file.

## Contributors
- Jesse Hausler
- Michael Kohanfars
- Hong Li
- Cordelia McGee-Tubb
- Bhargav Venkataraman